Comparison of Precipitation and Gel Combustion Methods for ZnO Nano Powder Preparation

One of the most important parameters, which affects on electrical properties of ZnO varistors, is the size of primary ZnO powder. There are various methods of preparing ZnO nano powders, but each has its own effect. In this research, two methods of precipitation and gel-combustion were used to prepare ZnO nano powder. In gel combustion method, fuel type and fuel to nitrate ratio were investigated while in precipitation method, the parameters such as pH and concentration were evaluated. The calcinations temperature was also studied for both methods. The results showed that the prepared ZnO nano powder from both methods are suitable for varistor application but the nano powder produced from gel combustion route has smaller size (30-50 nm) than precipitation (50-80 nm).

Keywords:

Zinc Oxide , Nano powder , Gel Combustion , Precipitation